Search engines typically execute searches against a homogenous set of items. Depending on the search engine, the homogenous set of items may be web pages, images, files, songs, videos, merchandise, etc. The type of item against which a search is executed is referred to herein as the “base type” of the search. Items that belong to the base type of a search are referred to herein as “base items”.
Objects that represent collections of base items are referred to herein as “collection items”. In some situations, collection items are themselves base items. For example, a “folder” is itself a file, but can also contain other files. Similarly, a web page may contain a listing of other web pages. Collection items that are base items are referred to herein as “base collection items”.
When a search engine performs a search against a particular base type, the search results may include base collection items as well as base items that are not collections. For example, the results of a search for files created on a particular date may include folders created on the specified date, as well as other files. Similarly, the results of a search for web-pages related to “Manhattan hotels” may include web pages for specific Manhattan hotels, as well as web pages from travel service sites that list web pages for Manhattan hotels.
Unfortunately, such base collection items are not the only collection items that would be useful to a searcher. In many cases, collections of base items have been specified in objects that are not themselves base items. For example, a user's set of “bookmarks” corresponds to a set of web pages, yet a bookmark set is not itself a web page. Consequently, bookmark sets are not listed in search results that are executed against web pages. Similarly, a user's playlist corresponds to a set of songs, but a playlist is not itself a song. Therefore, playlists are not listed in search results of searches that are executed against songs.
Collection items that are not themselves base items are referred to herein as “non-base collection items”. In some cases, the identification of relevant non-base collection items may be more useful to searchers than the identification of relevant base items. In other cases, the identification of relevant non-base collection items may be less useful than the identification of relevant base items. Therefore, it would be desirable to provide searchers with information about (a) relevant base items, (b) relevant base collection items, and (c) relevant non-base collection items, and to present the information in a manner that allows the searchers to determine the relative relevance of the various items.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.